Influence of quadrupole interaction on Fe-57 Mossbauer spectra for samples with charge- and spin-density waves

The influence of the quadrupole interaction on the shape of Fe-57 Mossbauer spectra expected for samples with charge-density waves and/or spin-density waves is investigated. It is shown, by model calculations, that both for the commensurate and for incommensurate charge-density waves and/or spin-density waves the shape of Fe-57 Mossbauer spectra is sensitive to the value, and for asymmetric spectra, to the sign of quadrupole interaction. This necessitates an inclusion of quadrupole interaction when analyzing the spectra recorded on samples exhibiting charge-density waves and/or spin-density waves, and having a symmetry lower than cubic.